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adultescent

American  
[ad-uhl-tes-uhnt, uh-duhl‑] / ˌæd ʌlˈtɛs ənt, əˌdʌl‑ /

noun

  1. a young adult or middle-aged person who has interests, traits, etc., that are usually associated with teenagers.


adultescent British  
/ ˌædəlˈtɛsənt /

noun

  1. an adult who is still actively interested in youth culture

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

adjective

  1. aimed at or suitable for adultescents

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of adultescent

First recorded in 1995–2000; adult + (adol)escent